胆囊收缩素A型受体基因序列变异和表达与略阳乌鸡饲料转化率的关联性研究  

Association of Levels of Cholecystokinin A Receptor Expression and Sequence Variants with Feed Conversion Efficiency of Lueyang Black-Boned Chicken

作　　者：王哲鹏[1] 周雯馨 贺俊锡 虎巧燕 赵家悦 WANG ZhePeng;ZHOU WenXin;HE JunXi;HU QiaoYan;ZHAO JiaYue(College of Animal Science and Technology,Northwest A&F University,Yangling 712100,Shaanxi)

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100

出　　处：《中国农业科学》2022年第22期4539-4549,共11页Scientia Agricultura Sinica

基　　金：陕西省重点研发计划(2021NY-028);略阳乌鸡蛋用型配套系选育(WJYJY-2021-3)。

摘　　要：【背景】食欲和饲料转化率的提高构成了现代肉鸡快速生长的生理基础。胆囊收缩素A型受体(CCKAR)是介导胆囊收缩素(CCK)饱食信号和消化调节作用的关键受体。鉴于CCK信号在能量平衡调节中的重要作用,CCKAR的表达水平与鸡的生长性能密切相关。然而,CCKAR水平调节鸡生长的确切机制尚不清楚。【目的】通过研究阐明CCKAR基因表达水平和序列变异与鸡饲料转化率的关系,为鸡生长性状遗传调控研究和饲料转化率选育奠定基础。【方法】测定略阳乌鸡12—16周龄料肉比(公鸡n=62,母鸡n=67)和26—30周龄料蛋比(n=150)。用PCR-RFLP法检测CCKAR基因内两个同义突变(g.73206714T>C和g.73209189C>T)的基因型。以性别为固定效应,用双因素方差分析检验g.73206714T>C和g.73209189C>T与料肉比的关联性,用单因素方差分析检验2个SNP与料蛋比的关联性。用JASPAR数据库预测g.73206714T>C对转录因子结合位点产生的影响。以g.73206714T>C为标记,选取10只杂合子(CT)公鸡,用PCR-RFLP法检测CCKAR基因在g.73206714T>C位点等位基因间的表达差异。选取30只带有采食量和料肉比记录的公鸡,用qPCR检测CCKAR基因在下丘脑、脑垂体、胰腺、胆囊和十二指肠中的表达水平,分析CCKAR表达水平与采食量和料肉比的相关性。【结果】性别效应对略阳乌鸡料肉比有显著影响(F=29.44,P<0.0001),公鸡的料肉比(5.41±0.76)显著低于母鸡(6.62±1.00)。在两个同义突变中,只有g.73206714T>C与料肉比显著关联(F=8.44,P=0.0004),其中,TT型的料肉比(5.18±0.63)显著低于CC(6.37±1.1)和CT型(6.17±0.95)。CC型和CT型的料肉比无显著差异。g.73206714T>C与性别的互作效应对料肉比的影响不显著。G.73206714T>C对28个转录因子结合位点有潜在影响。等位基因特异性表达试验显示,T等位基因的转录本丰度显著高于C等位基因,表明CCKAR在等位基因间的表达差异很可能是构成g.73206714T>C与料�【Background】Increased appetite and feed conversion efficiency forms a physiological basis underlying high growth of modern commercial broiler chickens.Cholecystokinin A receptor(CCKAR)is a key receptor for mediating CCK signals and involving in regulation of appetite and digestion.In view of the important role of CCK signals in the control of energy balance,the levels of CCKAR expression are closely related to the growth of chickens.However,the mechanism by which the abundance of CCKAR affects the growth of chickens remains unclear.【Objective】The aim of this study was to elucidate the relationship of levels of CCKAR expression and sequence variants with feed conversion efficiency,which would promote the understanding of genetic basis of the growth traits and breeding for improvement of feed efficiency in the chicken.【Method】The feed to meat conversion ratio of Lueyang black-boned chickens(rooster n=62,pullet n=67)from 12 to 16 weeks of age and the feed to egg conversion ratio from 26 to 30 weeks of age(n=150)were individually measured.Two synonymous mutations(g.73206714T>C and g.73209189C>T)in the CCKAR gene were genotyped by using PCR-RFLP.Association of two SNP with the feed to meat conversion ratio was tested by using two-way analysis of variance with sex treated as a fixed effect.Association of two SNP with the feed to egg conversion ratio was tested by using one-way analysis of variance.Disrupting effect of g.73206714T>C on transcription factor binding sites was predicted in silico by using JASPAR database.Ten birds that were heterozygotes(CT)at the g.73206714T>C locus were selected to analyze imbalance of CCKAR expression between T and C alleles.The difference of allele-specific expression was detected by using PCR-RFLP.The Levels of CCKAR expression were detected by qPCR in the hypothalamus,pituitary,pancreas,gallbladder and duodenum of Lueyang black-boned chickens(n=30).The correlation of levels of CCKAR expression with food intake and feed to meat conversion ratio was analyzed.【Result】Sex

关 键 词：鸡 生长 CCKAR 饲料转化率 食欲 

分 类 号：S831.5[农业科学—畜牧学]